Microlithographic structure with an underlayer film containing a thermolyzed azide compound

Abstract

Microlithographic methods for the use of improved underlayers for chemically amplified deep UV photoresist compositions and structures produced thereby are disclosed. The compositions comprise, in admixture, a polymeric binder, and an azide which is thermolyzed during microlithographic processing to form an amine. Films formed from the underlayer compositions of the present invention, when applied immediately under and proximate to a chemically amplified photoresist film reduce the resist structure sidewall foot or undercut caused by an adverse contact reaction.

What is claimed is: 
     
       1. A microlithographic structure comprising: a) a microlithographic substrate;   b) applied to the surface of said substrate, an underlayer film comprising a polymeric binder selected from the group consisting of polyarylether sulfones, polyarylether ketones, poly(vinyl naphthalenes), and polycarbonates and a basic species, wherein said basic species has been produced by thermolyzing a precursor of said basic species, wherein the precursor is an azide selected from the group consisting of 4,4'-diazidostilbene, 4,4'-diazidochalcone, 4,4'-diazidobenzophenone, 1,6-diazidopyrene, 4,4'-diazidodiphenylmethane, 3,3'-diazidodiphenyl sulfone, polymeric azides, and precursors comprising one or more phenylsulfonylazide substituents; and   c) overlaying said underlayer film, a chemically amplified photoresist film, wherein an acid is generated upon exposure to radiation.   
     
     
       2. The structure of claim 1 wherein the azide is 4,4'-diazidostilbene. 
     
     
       3. The structure of claim 1 wherein the azide is 4,4'-diazidochalcone. 
     
     
       4. The structure of claim 1 wherein the azide is 4,4'-diazidobenzophenone. 
     
     
       5. The structure of claim 1 wherein the azide is 1,6-diazidopyrene. 
     
     
       6. The structure of claim 1 wherein the azide is 4,4'-diazidodiphenylmethane. 
     
     
       7. The structure of claim 1 wherein the azide comprises one or more phenylsulfonylazide substituents. 
     
     
       8. The structure of claim 1 wherein said basic species is inherently absorbent of ultraviolet radiation, and wherein said underlayer film is an antireflective film. 
     
     
       9. The structure of claim 1 wherein said underlayer film is formed from a composition comprising from about 3 to about 10 wt.% of the precursor based on the weight of said polymeric binder. 
     
     
       10. The structure of claim 1 wherein said precursor is a polymeric azide. 
     
     
       11. The structure of claim 10 wherein the azide has a plurality of N 3  substituents.